1. Field of the Invention
The present invention relates generally to the field of multimedia communication, and specifically, to a method and apparatus for throttling connections to a H.323 multipoint controller by receiver terminals in a loosely-coupled conference.
2. Description of Related Art
Recommendation H.323, entitled "Visual Telephone Systems and Equipment for Local Area Networks Which Provide a Non-guaranteed Quality of Service", (version 1, published November 1996), describes terminals, equipment, and services for multimedia communication over local area networks ("LANs") and wide area networks ("WANs"). In particular, terminals compatible with Recommendation H.323 ("H.323 terminals") carry real-time voice, data, video, or any combination thereof including video telephony over a network (e.g., Internet). However, H.323 is limited in scalability due to the requirements for tightly-coupled conferencing. That is, H.323 requires that all participants in a conference be known in addition to a set of procedures for conference setup, capability negotiation, creation and control of audio/video/data streams, and conference tear down, all of which account for overhead. A central multipoint controller ("MC") is used for the aforementioned procedures. Such a procedure for conference setup and capability negotiation at the start of the conference, though essential for tightly-coupled conferences, is cumbersome and impractical for conferences involving an arbitrarily large number of participants. Potentially hundreds or thousands of receiver terminals can simultaneously attempt to connect to the MC. The MC allows a limited number of connection based on resources (i.e., memory, processing power, etc.) available for the conference. Some of the receiver terminals will successfully connect while others will unsuccessfully try to connect repeatedly, thereby congesting the MC.
Accordingly, there is a need in the art for a method and apparatus to throttle connections to a H.323 multipoint controller by receiver terminals in a loosely-coupled conference involving hundreds and thousands of participants.